The invention pertains to air bars for floating a running web so that the material, such as ink on a web is dried before the web contacts any support means. The invention is in the nature of an improvement over U.S. Pat. No. 3,549,070 which issued Dec. 22, 1970 to Frost et al and entitled "Floatation of Sheet Materials"; U.S. Pat. No. 3,873,013 which issued Mar. 15, 1975 to Paul H. Stibbe entitled "High Velocity Web Floating Air Bar having Central Exhaust Means"; U.S. Pat. No. 3,776,440 which issued Dec. 4, 1973 to Frost et al and entitled "Web Handling Apparatus"; or U.S. Pat. No. 3,964,656 which issued June 22, 1976 to Terry A. Hella, and entitled "Air Bar Assembly for Web Handling Apparatus."
In web drying equipment of the type shown in the above U.S. patents and others, pressurized air is introduced into the interior of the air bar and is then generally permitted to issue directly through transversely positioned, air discharge slots against the running web. Such prior devices sometimes caused nonuniform drying of the web across the web width due to the fact that the air was discharged from the slots unevenly along the length of the slots and in directions other than right angles to the transverse width of the web. The resulting cross machine momentum components of air movement resulted in uneven drying of the web across its width.